Dentro de los macroinvertebrados que habitan los ambientes dulceacuícolas, los insectos son el grupo biológico más idóneo para determinar la calidad del agua de los ecosistemas, ya sean lénticos o lóticos. Considerando la sensibilidad y la tolerancia intrínsecas de los insectos acuáticos, en este estudio se aplicó el índice biótico de Hilsenhoff (IBH, 1988) en las porciones alta, media y baja de 3 ríos perennes: Copalita, Zimatán y Coyula, Oaxaca. El IBH mostró en los 3 casos una calidad del agua de buena a muy buena.<br>Within the macroinvertebrates that inhabit in freshwaters, the insects are more suitable the biological group to establish the water quality of the lotic and lentic ecosystems. Considering the sensibility and tolerance intrinsic properties of the aquatic insects, in this study Hilsenhoff Biotic Index (HBI, 1988) was applied in the high, medium and low portions of 3 perennial rivers: Copalita, Zimatán and Coyula, Oaxaca, Mexico. The HBI showed in the 3 cases a good to very good water quality.

Within the macroinvertebrates that inhabit in freshwaters, the insects are more suitable the biological group to establish the water quality of the lotic and lentic ecosystems. Considering the sensibility and tolerance intrinsic properties of the aquatic insects, in this study Hilsenhoff Biotic Index (HBI, 1988) was applied in the high, medium and low portions of 3 perennial rivers: Copalita, Zimatán and Coyula, Oaxaca, Mexico. The HBI showed in the 3 cases a good to very good water quality.

Dentro de los macroinvertebrados que habitan los ambientes dulceacuícolas, los insectos son el grupo biológico más idóneo para determinar la calidad del agua de los ecosistemas, ya sean lénticos o lóticos. Considerando la sensibilidad y la tolerancia intrínsecas de los insectos acuáticos, en este estudio se aplicó el índice biótico de Hilsenhoff (IBH, 1988) en las porciones alta, media y baja de 3 ríos perennes: Copalita, Zimatán y Coyula, Oaxaca. El IBH mostró en los 3 casos una calidad del agua de buena a muy buena. | Within the macroinvertebrates that inhabit in freshwaters, the insects are more suitable the biological group to establish the water quality of the lotic and lentic ecosystems. Considering the sensibility and tolerance intrinsic properties of the aquatic insects, in this study Hilsenhoff Biotic Index (HBI, 1988) was applied in the high, medium and low portions of 3 perennial rivers: Copalita, Zimatán and Coyula, Oaxaca, Mexico. The HBI showed in the 3 cases a good to very good water quality.

O biomonitoramento é uma ferramenta utilizada para avaliar mudanças ocorridas na qualidade das águas de lagos e rios, através dos organismos vivos presentes naquele ambiente. Os macroinvertebrados bentônicos são classificados quanto à sua tolerância a mudanças na qualidade da água, podendo ser encontrados em ambientes naturais, alterados ou impactados. Na piscicultura, o biomonitoramento pode ser utilizado para avaliar as alterações ambientais provenientes de impactos externos ao sistema de produção ou para o diagnóstico da qualidade da água dentro da propriedade em busca da implantação de Boas Práticas de Manejo. Neste estudo, foram utilizados macroinvertebrados bentônicos como ferramenta para o biomonitoramento em viveiros escavados com produção de tilápia-do-Nilo (Oreochromis niloticus). Ao longo de três meses (fevereiro a maio de 2016), quatro pisciculturas do interior paulista, foram monitoradas quinzenalmente, observando-se a comunidade de macroinvertebrados bentônicos, e variáveis físicas e químicas de qualidade de água. Após tabulação os dados foram submetidos à ANOVA, programa estatístico que obtêm os valores de variâncias a partir dos dados transformados, foi aplicado o teste de Tukey para variáveis significativas das comunidades bentônicas e para as análises físicas e químicas. Resultados parciais revelaram que houve diferenças significativas entre as pisciculturas e as datas das coletas quinzenais para ambas variáveis bióticas e abióticas, e com destaque para a Família Chironomidae a qual foi mais abundante. Desse modo, já é possível afirmar que os períodos de coletas, pisciculturas e alguns parâmetros da água influenciam nas comunidades bentônicas, sendo que organismos mais resistentes possuem maior sucesso no estabelecimento de suas populações. Biomonitoring is a tool used to evaluate changes in the quality of lakes and rivers through the living organisms present in that environment. Benthic macroinvertebrates are classified according to their tolerance to changes in water quality, and can be found in natural, altered or impacted environments. In fish farming, biomonitoring can be used to evaluate environmental changes from external impacts to the production system or to the diagnosis of water quality within the property in search of the implementation of Good Management Practices (BPM). In this study, benthic macroinvertebrates were used as a tool for biomonitoring in nurseries excavated with Nile tilapia (Oreochromis niloticus) production. During three months (February to May 2016), four fish farms in the interior of São Paulo, were monitored biweekly, observing the community of benthic macroinvertebrates, and physical and chemical variables of water quality. After tabulation, the data were submitted to ANOVA, a statistical program that obtains the variance values from the transformed data, the Tukey test was applied for significant variables of the benthic communities and for the physical and chemical analyzes. Partial results revealed that there were significant differences between the fish farms and the biweekly collection dates for both biotic and abiotic variables, and the Chironomidae Family was the most abundant. Thus, it is possible to affirm that the collection periods, piscicultures and some parameters of the water influence the benthic communities, being that more resistant organisms are more successful in the establishment of their populations.

Sauce Lake, the main drinking water source in Maldonado, Uruguay, has been registering recurring events of potentially toxic cyanobacterial blooms that affect its service. This leads to the necessity of exploring the environmental drivers in the composition of phytoplankton, particularly in the presence of potentially toxic cyanobacteria. In this study we analyzed the environmental factors associated with phytoplankton composition and biomass, particularly of cyanobacteria. We sampled physicochemical variables, nutrients and phytoplankton during the summer 2015-2016 with a weekly frequency, in six sites of Sauce Lake. The results show a very high temporal and spatial variability in the phytoplankton composition, with cyanobacterial algal blooms of different taxa: Dolichospermum crassum, Cuspidothrix issatschenkoi, Microcystis aeruginosa, Microcystis panniformis y Sphaerocavum brasiliense. We observed that turbidity is a key factor controlling the total phytoplankton biomass, while the NT vs. PO4 concentrations determined the differential presence of potentially toxic cyanobacteria. The analysis of the relationship between these nutrients could contribute to anticipate different cyanobacterial harmful algal blooms in this ecosystem, enabling the development of management tools oriented to decrease its negative effects, particularly in the purification process. | Laguna del Sauce, principal fuente de agua para potabilización en Maldonado, Uruguay, ha registrado recurrentes eventos de floraciones de cianobacterias potencialmente tóxicas, que comprometen su uso como tal. Esto ha denotado la necesidad de un mayor conocimiento de los factores ambientales asociados a la composición fitoplanctónica y, en especial, a la ocurrencia de floraciones de cianobacterias. Mediante muestreos semanales estivales (2015-2016) de variables fisicoquímicas, nutrientes y fitoplancton, en seis sitios de Laguna del Sauce, se analizaron los factores ambientales asociados a la biomasa y composición fitoplanctónica, particularmente de cianobacterias. La alta variabilidad temporal y espacial observada en la composición fitoplanctónica presentó alternancia de floraciones de cianobacterias: Dolichospermum crassum, Cuspidothrix issatschenkoii, Microcystis aeruginosa, Microcystis panniformis y Sphaerocavum brasiliense. La turbiedad fue clave para regular la biomasa fitoplanctónica, mientras que la relación Nitrógeno total (NT):Ortofosfato (PO4) se asoció a la presencia diferencial de especies de cianobacterias. El análisis de las relaciones entre estos nutrientes puede contribuir a anticipar la ocurrencia de floraciones de diferentes especies de cianobacterias en este ecosistema, posibilitando la implementación de medidas de gestión orientadas a disminuir sus efectos adversos y, en particular, a asegurar el proceso de potabilización. &nbsp;

Tesis (M.Sc) –CATIE, Turrialba (Costa Rica), 2022 | Bajo el enfoque Una sola salud (One Health), la investigación busca mostrar la relación existente entre factores ambientales, la biología del entorno y el efecto que puede tener el uso del suelo, en especial la ganadería sobre la población a corto, medianoy largo plazo, monitoreado a través de los índices biológicos, como el BMWP’CR y el QBS-ar. La investigación se desarrolló en la franja ribereña de la quebrada La Mula (UTM 1148233N y 357966E), tomando como sitios de muestreo cuatro distintos usos del suelo. Los resultados presentan variaciones relacionadas con la estacionalidad y la presencia de vegetación adyacente a las franjas ribereñas en cada uno de los usos de suelo